JP2021134969A - Hot water storage type water heater - Google Patents

Abstract

To provide a hot water storage type water heater capable of appropriately solving a problem that a retention time of hot water in a hot water storage tank becomes long and thus the hot water becomes unsanitary, with a simple configuration.SOLUTION: A hot water storage type water heater A comprises an auxiliary heat source machine 3 that in a case where a main heat source U1, a hot water storage tank 2 and a bathtub 91 are filled with hot water, heats hot water supplied from the outside without passing through the hot water storage tank 2 when the temperature of the hot water in the hot water storage tank 2 is insufficient, and enables hot water to be discharged to the bathtub 91. In a case where a retention time of at least part of the hot water in the hot water storage tank 2 exceeds a predetermined time Ta, when the bathtub 91 is filled with hot water, a predetermined amount of hot water in the hot water storage tank 2 is supplied to the bathtub 91 regardless of whether or not the temperature of the hot water in the hot water storage tank 2 is insufficient.SELECTED DRAWING: Figure 1

Description

The present invention relates to a hot water storage type hot water supply device including a hot water storage tank.

The applicant has previously proposed the ones described in Patent Documents 1 and 2 as specific examples of the hot water storage type hot water supply device.
The hot water storage type hot water supply device described in these documents is a hot water storage tank that stores hot water heated by using a main heat source and can be used for filling a bathtub or for other general hot water supply. , And an auxiliary heat source machine. The auxiliary heat source machine is a hot water supplied through a flow path that does not pass through the hot water storage tank when the temperature is insufficient, for example, the temperature of the hot water in the hot water storage tank is lower than the target temperature for filling the bathtub. Alternatively, the hot water discharged from the hot water storage tank can be heated. According to such a configuration, it is possible to appropriately eliminate the difficulty in supplying hot water at a desired temperature when the hot water storage tank is in a so-called running-out state.

Here, Patent Document 1 has a configuration in which hot water discharged from a hot water storage tank can be heated by an auxiliary heat source machine. On the other hand, Patent Document 2 does not provide means for sending the hot water in the hot water storage tank to the auxiliary heat source machine (corresponding to the pipe 68 and the valve V3 shown by the virtual line in FIG. 1 to be described later). The hot water discharged from the hot water storage tank cannot be heated by the auxiliary heat source machine. In Patent Document 2, when the temperature of the hot water in the hot water storage tank is insufficient, the hot water is supplied from the outside to the auxiliary heat source machine and the hot water is heated. According to such a configuration of Patent Document 2, since the piping for sending the hot water in the hot water storage tank to the auxiliary heat source machine is unnecessary, the overall device configuration can be simplified and the manufacturing cost can be reduced accordingly. It is possible.

However, the configuration described in Patent Document 2 described above has the following problems.

That is, in Patent Document 2, if the temperature of the hot water in the hot water storage tank is insufficient, the hot water in the hot water storage tank is not used for hot water supply and is not discharged. Therefore, as compared with Patent Document 1, for example, the hot water in the hot water storage tank is not discharged. The frequency of replacement is low, and the residence time of hot water in the hot water storage tank tends to be long. If the residence time is considerably long, various germs such as Legionella may propagate and become unsanitary.
On the other hand, conventionally, when the residence time of hot water in the hot water storage tank reaches a predetermined retention limit time, there is a means for sending the hot water in the hot water storage tank to the main heat source to heat it and perform sterilization treatment. By adopting such means, the above-mentioned problems can be appropriately solved, but in Patent Document 2, the frequency with which the residence time reaches a predetermined residence limit time, and eventually the frequency with which hot water is sterilized increases. .. This is disadvantageous in terms of energy saving, and inconvenience occurs because the hot water in the hot water storage tank cannot be used for hot water supply during the sterilization process.

Japanese Unexamined Patent Publication No. 2014-25681 Japanese Unexamined Patent Publication No. 2014-9894 Japanese Patent No. 6252762 Japanese Patent No. 4981777

The present invention has been conceived under the above-mentioned circumstances, and it is possible to appropriately solve the problem that the residence time of hot water in the hot water storage tank becomes long and becomes unsanitary by a simple configuration. The challenge is to provide a hot water storage type hot water supply device that is possible.

In order to solve the above problems, the following technical measures are taken in the present invention.

The hot water storage type hot water supply device provided by the present invention has a hot water storage tank that stores hot water heated by using a main heat source and can discharge hot water to the bathtub, and hot water filling the bathtub. When the temperature of the hot water in the hot water storage tank is insufficient, the hot water supplied from the outside without passing through the hot water storage tank is heated so that the hot water for filling the bathtub can be discharged. When the residence time of at least a part of the hot water in the hot water storage tank exceeds a predetermined time in the hot water storage type hot water supply device equipped with the auxiliary heat source machine, the bathtub is filled with hot water. At that time, regardless of whether or not the temperature of the hot water in the hot water storage tank is insufficient, a predetermined amount of hot water in the hot water storage tank is configured to be supplied to the bathtub.

According to such a configuration, the following effects can be obtained.
That is, when the residence time of at least a part of the hot water in the hot water storage tank exceeds the predetermined time, the predetermined amount of hot water in the hot water storage tank is irrespective of whether or not the temperature of the hot water in the hot water storage tank is insufficient. Is supplied to the bathtub, so that the replacement of hot water in the hot water storage tank is promoted, and it becomes possible to prevent hot water having a long residence time from existing in the hot water storage tank. Therefore, it is possible to prevent the growth of various germs such as Legionella and make it hygienic.
According to the present invention, when a means for sterilizing the hot water in the hot water storage tank by heating the hot water in the hot water storage tank when the residence time of the hot water in the hot water storage tank becomes long is adopted, the frequency of the sterilization treatment is performed. Is reduced. Therefore, it is possible to save energy. In addition, the inconvenience of making it difficult to use the hot water in the hot water storage tank during the sterilization process is eliminated or alleviated.

In the present invention, preferably, when the bathtub is filled with hot water, if the temperature of the hot water in the hot water storage tank is insufficient, the hot water is heated by the hot water discharged from the hot water storage tank and the auxiliary heat source machine. It is configured to be mixed with hot water and supplied to the bathtub.

According to such a configuration, the following effects can be obtained.
That is, when the temperature of the hot water in the hot water storage tank is insufficient, for example, if only the hot water in the hot water storage tank is used for filling the bathtub, the temperature of the hot water filled in the bathtub may be considerably lowered. On the other hand, according to the above configuration, the temperature of the hot water filled in the bathtub can be made higher than the temperature of the hot water in the hot water storage tank, and the above-mentioned possibility can be eliminated.

In the present invention, preferably, when the bathtub is filled with hot water, if the temperature of the hot water in the hot water storage tank is insufficient, the hot water heated by the auxiliary heat source machine is further supplied to the bathtub. Alternatively, the hot water in the bathtub is reheated so that the hot water in the bathtub is set to a predetermined hot water filling target temperature.

According to such a configuration, when the temperature of the hot water in the hot water storage tank is insufficient, even if this hot water is used to fill the bathtub, the hot water in the bathtub is finally used as the predetermined hot water. The tension target temperature can be set appropriately.

In the present invention, preferably, when the residence time of at least a part of the hot water in the hot water storage tank exceeds the predetermined time, the amount of the retained hot water whose residence time exceeds the predetermined time is obtained, and this An amount equal to or greater than the amount of retained hot water is configured to be the predetermined amount.

According to such a configuration, among the hot water existing in the hot water storage tank, all or more of the hot water having a residence time exceeding a predetermined time is supplied to the bathtub when the bathtub is filled with hot water. Therefore, when the filling of the bathtub with hot water is completed, the hot water whose residence time exceeds the predetermined time does not remain in the hot water storage tank.

In the present invention, preferably, when the residence time of at least a part of the hot water in the hot water storage tank exceeds the predetermined time, the amount of the retained hot water whose residence time exceeds the predetermined time can be obtained, and at present. If it is planned or predicted that the bathtub is filled with hot water multiple times during the period from to the predetermined residence limit time, the amount is equal to or greater than the amount of the retained hot water. The hot water is supplied from the hot water storage tank to the bathtub in a state of being subdivided for each of the plurality of hot water filling operations in the bathtub.

According to such a configuration, among the hot water existing in the hot water storage tank, the hot water having a residence time exceeding a predetermined time is subdivided for each of a plurality of hot water filling operations in the bathtub under a predetermined condition. Since the hot water is supplied to the bathtub in a state, it is possible to prevent a large amount of hot water in the hot water storage tank from being supplied to the bathtub at one time. Therefore, the possibility that the temperature of the hot water filled in the bathtub becomes considerably low is reduced, and the conditions when the hot water filling operation in the bathtub is executed a plurality of times are made uniform (for example, so-called uniforming of the bath boiling time). It becomes possible.

In the present invention, preferably, a means capable of setting a hot water replacement promotion mode for promoting the replacement of hot water in the hot water storage tank is further provided, and when the hot water replacement promotion mode is set, the above-mentioned Whether or not the residence time of at least a part of the hot water in the hot water storage tank exceeds the predetermined time when the bathtub is filled with hot water, and whether or not the temperature of the hot water in the hot water storage tank is insufficient. Regardless of the above, at least a part of the hot water in the hot water storage tank is configured to be supplied to the bathtub.

According to such a configuration, when the hot water replacement promotion mode is set, the hot water replacement in the hot water storage tank is further promoted, and the needs of users who desire such a situation are accurately met. It is possible to make it.

Other features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings.

It is a schematic explanatory drawing which shows an example of the hot water storage type hot water supply apparatus which concerns on this invention. It is a flowchart which shows an example of the operation processing procedure executed by the hot water storage type hot water supply apparatus shown in FIG. It is a flowchart which shows another example of the operation processing procedure executed by the hot water storage type hot water supply apparatus shown in FIG. It is a flowchart which shows another example of the operation processing procedure executed by the hot water storage type hot water supply apparatus shown in FIG.

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

The hot water storage type hot water supply device A shown in FIG. 1 includes a heat pump unit U1 and a hot water storage tank unit U.
It is configured as a heat pump type hot water supply device configured by combining 2 and 2.

The heat pump unit U1 corresponds to an example of the main heat source according to the present invention, and includes a heat pump 1, a control unit (not shown) for controlling the heat pump 1. The heat pump 1 is the same as that conventionally known, for example, an evaporator 10, a compressor 11, and a hot water heater for absorbing heat from air taken in by using a fan 10a in a circulation path of a refrigerant such as _{CO 2.} A condensate heat exchanger 12 (condenser) and an expansion valve 13 are provided.

The hot water storage tank unit U2 includes a hot water storage tank 2, an auxiliary heat source machine 3, a control unit 4, and the like.

The lower part and the upper part of the hot water storage tank 2 are connected (pipe connection) to the condensing heat exchanger 12 of the heat pump 1 via the hot water flow path 5a and the hot water return flow path 5b. By driving the circulation pump P1 provided in the hot water outflow flow path 5a, the hot water flowing out from the lower part of the hot water storage tank 2 to the hot water outflow flow path 5a is sent to the condensing heat exchanger 12 to be heated, and this The heated hot water is returned to the upper part in the hot water storage tank 2 via the hot water return flow path 5b, and is stored. A plurality of temperature sensors Sa are mounted on the hot water storage tank 2, and the control unit 4 can determine the amount of hot water stored (heat storage amount) in the hot water storage tank 2 based on the detection signals from these temperature sensors Sa.

A water inlet pipe 61 having a water inlet 61a and a hot water outlet pipe 62 having a hot water outlet 62a are separately connected to the lower part and the upper part of the hot water storage tank 2. The hot water tap 90 connected to the hot water outlet 62a by a pipe is opened, and the hot water in the hot water storage tank 2 flows out to the hot water pipe 62, so that the hot water is supplied toward the hot water tap 90 (general hot water supply).

In the hot water storage tank unit U2, in addition to the general hot water supply described above, it is possible to fill the bathtub 91 with hot water, reheat the bath, and supply hot water (heat medium) to the heating terminal 92 for heating operation. When the temperature of the hot water in 2 is insufficient, it is possible to supplement the insufficient heat amount by using the auxiliary heat source machine 3.
Specifically, the hot water storage tank unit U2 is provided with a flow path 63 for guiding the hot water discharged from the hot water storage tank 2 to the bathtub 91 and an on-off valve V1. By opening the on-off valve V1. , It is possible to supply hot water (filled with hot water) to the bathtub 91. Further, a heat medium circulation flow path 64 and a heat exchanger 8b having a circulation pump P2 and a heat exchanger 8a for reheating the bath, a circulation pump P3 for the heating terminal 92, and various hot water flow paths related thereto. , Valves, pumps, etc. are further provided.

The auxiliary heat source machine 3 is similar to, for example, a gas instantaneous water heater, in which the burner 30 and the heat exchanger 31 are housed in the can body 32, and the hot water supplied to the heat exchanger 31 via the pump P4 is burned. It is configured so that it can be heated quickly by 30. The hot water storage tank unit U2 is not provided with means (means corresponding to the pipe 68 and the valve V3 shown by the virtual line) capable of guiding the hot water discharged from the hot water storage tank 2 to the auxiliary heat source machine 3. The auxiliary heat source machine 3 has a mode in which the hot water that has entered the water inlet 61a and has flowed into the auxiliary heat source machine 3 without passing through the hot water storage tank 2 is heated, and the heated hot water is discharged from the hot water outlet 62a. Hot water supply operation is possible.

The control unit 4 is configured by using a microcomputer or the like, and executes operation control and data processing of each part of the hot water storage tank unit U2. As will be described later, the residence time of hot water in the hot water storage tank 2 is predetermined. Control is also performed so that the residence limit time is not exceeded.

A remote controller 40 is communicated with the control unit 4. The remote controller 40 has a data display unit 41, a plurality of operation switches 42, and the like, and by operating the operation switches 42, for example, a hot water replacement promotion mode described later can be set. The control unit 4 has a learning ability to predict future heat demand based on the past heat demand (hot water supply operation record), and can automatically start the hot water filling operation to the bathtub 91 at an appropriate timing. It is possible.

Next, the operation processing procedure executed in the hot water storage type hot water supply device A will be described with reference to the flowchart shown in FIG. At the same time, the action at that time will be described.

First, the control unit 4 periodically determines the residence time of hot water (oldest hot water) in the hot water storage tank 2 (S1). The residence time of hot water can be calculated from the volume of the hot water storage tank 2, the amount of hot water discharged from the hot water storage tank 2, the hot water discharge time (same as the water entry time from the lower part into the hot water storage tank 2), and the current time information. be. After the residence time of hot water is determined, this is compared with Ta for a predetermined time (S2). This predetermined time Ta is shorter than the predetermined residence limit time, but if the hot water is present in the hot water storage tank 2 for a longer time than that, there is a risk that various germs such as Legionella bacteria will propagate. It is a time that occurs and is considered unfavorable for hygiene.

As a result of the above comparison, when the residence time of hot water does not exceed the predetermined time Ta, no special control is performed. That is, in this case, when the bathtub 91 is subsequently filled with hot water, normal control is executed, and if the hot water in the hot water storage tank 2 is insufficient in temperature with respect to the hot water filling target temperature, the auxiliary heat source machine Hot water heated using 3 is supplied to the bathtub 91 (S2: NO, S9: YES, S10: YES, S11). On the other hand, when the temperature of the hot water in the hot water storage tank 2 is not insufficient, the hot water in the hot water storage tank 2 is supplied to the bathtub 91 and filled with hot water (S10: NO, S12).

On the other hand, when the residence time of the hot water exceeds Ta for a predetermined time, the following processing is performed when the hot water filling the bathtub 91 is started (S2: YES, S3: YES).
First, before actually starting the filling of the bathtub 91 with hot water, the amount Q of the hot water (retained hot water) in the hot water storage tank 2 whose residence time exceeds Ta for a predetermined time is obtained (S4). This amount Q can be obtained based on the volume of the hot water storage tank 2 and the amount of hot water discharged from the hot water storage tank 2.

Next, regardless of whether the hot water in the hot water storage tank 2 is insufficient in temperature with respect to the hot water filling target temperature, the amount of hot water equal to or greater than the amount Q of the retained hot water is discharged from the hot water storage tank 2. The hot water is discharged (S5). As a result, the entire amount of hot water whose residence time exceeds Ta for a predetermined time is discharged from the hot water storage tank 2, and the hygienic state in the hot water storage tank 2 can be appropriately maintained.
In this hot water storage type hot water supply device A, when the residence time of the hot water in the hot water storage tank 2 reaches the above-mentioned retention limit time, the hot water in the hot water storage tank 2 is heated by using the heat pump unit U1 to perform sterilization treatment. It is possible to apply the means for applying, but in this case, according to the present embodiment, the frequency of the sterilization treatment can be reduced, and the running cost can be reduced.

In step S5 described above, preferably, when hot water is discharged from the hot water storage tank 2, the heated hot water is mixed by using the auxiliary heat source machine 3. As a result, even when the temperature of the hot water in the hot water storage tank 2 is low, it is possible to supply the hot water to the bathtub 91 at a hot water filling target temperature or a temperature close to the target temperature. This is advantageous in eliminating reheating for bringing the hot water filled in the bathtub 91 to a predetermined hot water filling target temperature after filling with hot water, or shortening the reheating time.

After the hot water filling (dropping) into the bathtub 91 was completed, the hot water temperature of the bathtub 91 was confirmed, and if it was lower than the hot water filling target temperature, it was heated by reheating or by using the auxiliary heat source machine 3. By supplying the hot water to the bathtub 91, the hot water temperature of the bathtub is set to the hot water filling target temperature (S6: YES, S7, S8).

In this hot water storage type hot water supply device A, it is possible to further execute the operation control as shown in FIGS. 3 and 4.

In the flowchart shown in FIG. 3, steps S1 to S4 are the same as those in FIG. In the operation control shown in FIG. 3, when the residence time of the hot water in the hot water storage tank 2 exceeds the predetermined time Ta, when the bathtub 91 is filled with hot water, the current time is set to the predetermined residence limit time. The number of times the bathtub 91 is filled with hot water until it is reached is determined (S21). This determination is made based on the learning function of the control unit 4, the reservation information for filling the bathtub 91 in the bathtub 91 set by using the remote controller 40, and the like. As a result of this determination, when the bathtub 91 is filled with hot water only once, the same control as in steps S5 and subsequent steps of FIG. 2 is executed (S22: NO).

On the other hand, when the bathtub 91 is filled with hot water a plurality of times, the amount of hot water discharged from the hot water storage tank 2 toward the bathtub 91 when the bathtub 91 is filled with hot water is determined in step S4. The quantity Q is divided into a plurality of times (S22: YES, S23). Of course, the hot water discharged from the hot water storage tank 2 is executed regardless of whether or not the hot water in the hot water storage tank 2 is insufficient in temperature with respect to the hot water filling target temperature.

According to such operation control, it is possible to prevent a large amount of hot water in a temperature insufficient state from being supplied from the hot water storage tank 2 to the bathtub 91 at the time of filling the bathtub 91 with hot water once. Therefore, it is possible to prevent the temperature of the hot water filled in the bathtub 91 from becoming considerably low. If a large amount of hot water in an insufficient temperature state is supplied to the bathtub 91 at one time, it may take a long time to reheat the hot water and raise it to the hot water filling target temperature. It is possible to eliminate such a risk.

In the operation control shown in FIG. 4, when filling the bathtub 91 with hot water, the control unit 4 is configured to determine whether or not the hot water replacement promotion mode is set (S31: YES, S32). ). Here, the hot water replacement promotion mode is a mode for promoting the replacement of hot water in the hot water storage tank 2, and as described above, it can be set by operating, for example, the remote controller 40. When this hot water replacement promotion mode is set, whether or not the residence time of hot water in the hot water storage tank 2 exceeds the above-mentioned predetermined time Ta when the bathtub 91 is filled with hot water, and whether or not the hot water is stored. Regardless of whether or not the temperature of the hot water in the tank 2 is insufficient, at least a part of the hot water in the hot water storage tank 2 is supplied to the bathtub 91 (S32: YES, S33).

When the hot water replacement promotion mode is set, the hot water replacement in the hot water storage tank 2 is further promoted, which is preferable for the user who desires such a thing.
On the other hand, unlike the above, when the hot water replacement promotion mode is not set, the above-described operation control shown in FIG. 2 is executed (S32: NO).

The present invention is not limited to the contents of the above-described embodiments. The specific configuration of each part of the hot water storage type hot water supply device according to the present invention can be variously redesigned within the scope intended by the present invention.
As the main heat source, other devices / devices such as a gas engine system equipped with a heat exchanger capable of heating hot water and a fuel cell unit can be used instead of the heat pump unit.

A Hot water storage type hot water supply device U1 Heat pump unit (main heat source)
U2 Hot water storage tank unit 1 Heat pump 2 Hot water storage tank 3 Auxiliary heat source machine 4 Control unit 40 Remote control (means that can set hot water replacement promotion mode)
91 bathtub

Claims (6)

A hot water storage tank that stores hot water heated using the main heat source and allows hot water to be discharged to the bathtub.
When the bathtub is filled with hot water and the temperature of the hot water in the hot water storage tank is insufficient, the hot water supplied from the outside without passing through the hot water storage tank is heated to fill the bathtub with hot water. Auxiliary heat source machine that enables hot water to be discharged
It is a hot water storage type hot water supply device equipped with
When the residence time of at least a part of the hot water in the hot water storage tank exceeds a predetermined time, whether or not the temperature of the hot water in the hot water storage tank is insufficient when the bathtub is filled with hot water. Regardless, the hot water storage type hot water supply device is configured to supply a predetermined amount of hot water in the hot water storage tank to the bathtub. The hot water storage type hot water supply device according to claim 1.
If the temperature of the hot water in the hot water storage tank is insufficient when the bathtub is filled with hot water, the hot water discharged from the hot water storage tank and the hot water heated by the auxiliary heat source machine are mixed and described. A hot water storage type hot water supply device that is configured to be supplied to the bathtub. The hot water storage type hot water supply device according to claim 1 or 2.
If the temperature of the hot water in the hot water storage tank is insufficient when the bathtub is filled with hot water, the hot water heated by the auxiliary heat source machine is further supplied to the bathtub, or the hot water in the bathtub is chased. A hot water storage type hot water supply device configured so that the hot water in the bathtub is set to a predetermined hot water filling target temperature by being heated. The hot water storage type hot water supply device according to any one of claims 1 to 3.
When the residence time of at least a part of the hot water in the hot water storage tank exceeds the predetermined time, the amount of the retained hot water whose residence time exceeds the predetermined time is obtained and is the same as or equal to the amount of the retained hot water. A hot water storage type hot water supply device in which a larger amount is configured to be the predetermined amount. The hot water storage type hot water supply device according to any one of claims 1 to 4.
When the residence time of at least a part of the hot water in the hot water storage tank exceeds the predetermined time, the amount of the retained hot water whose residence time exceeds the predetermined time is obtained, and from the present time to the predetermined residence limit time. If it is planned or predicted that the hot water filling operation to the bathtub will be performed a plurality of times during the period of A hot water storage type hot water supply device configured to be supplied from the hot water storage tank to the bathtub in a state of being subdivided according to the operation of filling the bathtub with hot water. The hot water storage type hot water supply device according to any one of claims 1 to 5.
Further, it is provided with a means capable of setting a hot water replacement promotion mode for promoting the replacement of hot water in the hot water storage tank.
When the hot water replacement promotion mode is set, whether or not the residence time of at least a part of the hot water in the hot water storage tank exceeds the predetermined time when the bathtub is filled with hot water. A hot water storage type hot water supply device configured to supply at least a part of the hot water in the hot water storage tank to the bathtub regardless of whether or not the hot water in the hot water storage tank is insufficient in temperature.

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